1. Field of the Invention
The present invention relates generally to knee braces for injured or weakened knees, and, more particularly, to functional knee braces of the type suitable for athletes having weakened or torn knee ligaments, or other substantial knee injury.
2. Background of the Invention
In the orthopaedic knee brace or support field, relatively simple knee braces may be used for normal postoperative recovery, or for minor knee problems or injuries.
However, for major knee injuries, and/or when the user wishes to engage in vigorous athletic activities, a carefully molded functional knee brace is often prepared. The process for making these functional knee braces is moderately complicated, and involves initially making a mold of the users leg, and subsequently casting fiber reinforced resin to form the femoral (upper leg) and tibial (lower leg) components which are joined by struts and suitable hinge or pivot arrangements of known configurations. These preparation steps are time-consuming, complicated, and expensive.
Many techniques and systems have been proposed to reduce the weight and bulk of the knee brace, while insuring a snug fit. While many patented orthopaedic knee braces have claimed these improvements, in fact, none has disclosed a custom "in situ" formable knee brace having a low-weight, low-bulk profile. Instead, many of the patented designs require a multiplicity of securing straps and layers of foam rubber, thereby resulting in increased bulk and weight. Moreover, the so-called customized fit is achieved by wrapping one or more layers of foam rubber, having generic dimensions, around the unique configuration of an individual's upper and lower leg, and securing the foam wrapping by the use of numerous adjustable securing straps.
Reference is made to U.S. Pat. Nos. 4,852,557, 41928,678, and 4,996,979, which provide formable orthopaedic cast or splint systems adapted to the unique configuration of an injured or broken limb. These splint systems, however, are directed exclusively to immobilizing a single straight limb, such as the lower arm or lower leg. Further, these designs may require supplemental support splints or ribs to provide the requisite degree of rigidity. In addition, these references disclose formable members which are adapted to surfaces requiring minimal curvature; the desired custom fit resulting from a wrappable foam sleeve and an inter-meshing hook and loop fastener material (commonly known as "VELCRO") strap system, rather than from the formable member.
Further reference is made to U.S. Pat. No. 5,042,464 to Skwor et al. which discloses the use of rigid cuffs and a formed resilient pad which is intended to accommodate the differences in configuration between the standard configuration rigid cuffs and the user's leg shape. The orthotic knee brace of Skwor et al. discloses a pad which includes a conformable, pliable, curable foam sheet. Not only is the pad initially pliable when placed around the user's leg, but the pad remains resilient even after it is cured. Accordingly, Skwor et al. teach the use of a resilient pad with a standard rigid curved cuff member, a structural combination which does not, in general actually match the shape of the user's leg, which does not provide optimal support, and which additionally requires cumbersome mechanical fasteners.
Accordingly, principal objectives of the present invention are to provide an orthopaedic custom "in situ" formable knee brace suitable for vigorous athletic activities which is lightweight, truly, uniquely and completely formable to the individual's leg and knee configuration, and easily fitted and removed. Additional objectives of the present invention are to provide a custom formable knee brace which is simpler to fabricate, may be custom formed "in situ" in a short time, is formed to the shape of the thigh and calf in its entirety and becomes substantially rigid in its conformation to the shape of the leg of the user, and is significantly less expensive than functional braces made in accordance with conventional methods, such as those described hereinabove. In accomplishing these objectives, the invention will increase the stability of the weakened or injured knee joint and insure the prevention of undesirable movements which could further injure the knee joint or complicate its healing.